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Delivery: <= 4 days. True-PDF full-copy in English will be manually translated and delivered via email. GB/T 20724-2021: Microbeam analysis - Method of thickness measurement for thin crystals by convergent beam electron diffraction Status: Valid GB/T 20724: Historical versions
Basic dataStandard ID: GB/T 20724-2021 (GB/T20724-2021)Description (Translated English): Microbeam analysis - Method of thickness measurement for thin crystals by convergent beam electron diffraction Sector / Industry: National Standard (Recommended) Classification of Chinese Standard: N53 Word Count Estimation: 21,284 Issuing agency(ies): State Administration for Market Regulation, China National Standardization Administration GB/T 20724-2021: Microbeam analysis - Method of thickness measurement for thin crystals by convergent beam electron diffraction---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order. Microbeam analysis -- Method of thickness measurement for thin crystals by convergent beam electron diffraction ICS 71:040:99 CCSN53 National Standards of People's Republic of China Replacing GB/T 20724-2006 Microbeam Analysis of Thin Crystal Thickness Converging beam electron diffraction measurement method Published on 2021-12-31 2022-07-01 Implementation State Administration for Market Regulation Released by the National Standardization Administration directory Preface III Introduction IV 1 Scope 1 2 Normative references 1 3 Terms and Definitions 1 4 Method overview 3 5 Instruments 4 5:1 Main equipment 4 5:2 Data recording and measurement methods 4 6 Sample 4 6:1 General requirements 4 6:2 Thin Crystal Specimens 4 6:3 Extraction of replicas or powder samples 4 7 Experimental Step 4 7:1 Instrument Preparation 4 7:2 Obtaining the double-beam converging beam electron diffraction pattern 5 7:3 Data Measurement and Calculation 6 8 Uncertainty of measurement results7 9 Experiment report 8 Appendix A (Informative) Example of Converging Beam Electron Diffraction Measurement of Thin Silicon Crystal Thickness 9 A:1 Sample 9 A:2 Experimental Conditions and Parameters 9 A:3 Experimental Results and Data Analysis 9 A:4 Measurement results 15 Reference 16 forewordThis document is in accordance with the provisions of GB/T 1:1-2020 "Guidelines for Standardization Work Part 1: Structure and Drafting Rules of Standardization Documents" drafted: This document replaces GB/T 20724-2006 "Method for Determination of Thickness of Thin Crystals by Converging Beam Electron Diffraction", and GB/T 20724-2006 In contrast, except for structural adjustments and editorial changes, the main technical changes are as follows: a) Added some terms and definitions (see Chapter 3); b) Added requirements for instrument preparation (see 7:1); c) Changed the steps for experimental determination in TEM mode (see 7:2:1, 7:2 of the:2006 edition); d) An example diagram of the selected area electron diffraction pattern and its index calibration has been added (see Figure 2 in 7:2:1); e) Added the STEM mode for acquiring convergent beam diffraction patterns (see 7:2:2); f) The method of data measurement and calculation has been changed (see 7:3, 7:6 of the:2006 edition); g) Changed the method of finding the thickness of thin crystals by linear fitting method (see 7:3:3, 7:3:4, Chapter 8 of the:2006 edition); h) The requirements for the format of the experimental report have been deleted (see Chapter 9 of the:2006 edition); i) added uncertainty analysis (see Chapter 8); j) Changed the requirements for the content of the experimental report (see Chapter 9, Chapter 9 of the:2006 edition): Please note that some content of this document may be patented: The issuing agency of this document assumes no responsibility for identifying patents: This document is proposed and managed by the National Microbeam Analysis Standardization Technical Committee (SAC/TC38): This document is drafted by: Beijing University of Science and Technology, China Aviation Development Beijing Institute of Aeronautical Materials: The main drafters of this document: Liu Delu, Lou Yanzhi: This document was first published as GB/T 20724-2006 in:2006, and this is the first revision:IntroductionThe research and development of a large number of new materials, as well as the evaluation and control of performance characteristics, require microstructure characteristics on the micro and nano scales: Carry out analytical determination, especially the determination of the thickness of thin crystal samples or nano-scale powders, particles and other materials: Methods for measuring the thickness of thin crystals are Several, current Converging Beam Electron Diffraction (CBED) methods can measure the relative standard deviation of the thickness of thin crystals up to To about 2%, it is a very important method in material analysis: At present, our country is analyzing and testing in scientific research institutes, colleges and universities, large enterprises and various provinces and cities: The laboratories in the test center and other places are equipped with many transmission electron microscopes/scanning transmission electron microscopes (TEM/STEM), electron diffraction techniques: It is widely used in the analysis and research of various materials, especially new materials and nanomaterials: In order to standardize the method of applying the converging beam electron diffraction technique to determine the thickness of thin crystals of materials, GB/T 20724- In:2006, the standard has been implemented for more than ten years: During this period, the research level of materials, analysis technology and instruments and equipment have been greatly developed and improved: In particular, the development and application of new materials puts forward higher requirements for microbeam analysis methods: In order to adapt to the development of my country's science and technology and industrialization Trends demand for materials science and microscopic analysis, GB/T 20724-2006 has been revised: Microbeam Analysis of Thin Crystal Thickness Converging beam electron diffraction measurement method1 ScopeThis document describes Converged Beam Electron Diffraction for Thickness Measurement of Thin Crystal Specimens Using Transmission Electron Microscopy/Scanning Transmission Electron Microscopy method: This document is suitable for the determination of thin crystal samples with linearity ranging from tens of nanometers to hundreds of micrometers and thicknesses in the range of tens of nanometers to hundreds of nanometers: thickness: Note: Since the thickness of thin specimens for transmission electron microscopy is often non-uniform, what is measured by the method of convergent beam diffraction is the local thickness of the specimen illuminated by the electron beam:2 Normative referencesThe contents of the following documents constitute essential provisions of this document through normative references in the text: Among them, dated citations documents, only the version corresponding to that date applies to this document; for undated references, the latest edition (including all amendments) applies to this document: GB/T 18907-2013 Microbeam Analysis and Analysis Electron Microscopy Transmission Electron Microscope Selected Area Electron Diffraction Analysis Method GB/T 27418-2017 Evaluation and representation of measurement uncertainty ISO 15932:2013 Microbeam analysis-Analytical electron microscopy terminology (Microbeamanalysis-Analyticalelectron microscopy-Vocabulary)3 Terms and DefinitionsISO 15932:2013 and the following terms and definitions apply to this document: 3:1 convergent beam electron diffraction; CBED A technique for obtaining diffraction patterns using a converging electron beam: Note: Due to the large aperture angle of the incident electron beam (usually greater than 10-3rad), the diffraction pattern is composed of a diffraction disc with a certain size and a direct disc: A fringe contrast occurs within the diffraction disk: [Source: ISO 15932:2013, 8:3:6, with modifications] 3:2 thincrystalspecimen It can be placed on the sample stage of the transmission electron microscope, and the incident electron beam can penetrate the crystal sample: 3:3 Selected Area Electron Diffractionselectedareaelectrondiffraction;SAED In transmission electron microscopy, a diffraction pattern is obtained by selecting a sample area with a selective aperture located in front of the intermediate mirror: [Source: ISO 15932:2013, 8:3:4, with modifications] 3:4 Bragg diffraction Braggdiffraction Diffraction of an incident electron beam at specific angles relative to the atomic plane of the crystal due to constructive interference: ......Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of GB/T 20724-2021_English be delivered?Answer: Upon your order, we will start to translate GB/T 20724-2021_English as soon as possible, and keep you informed of the progress. 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